GB1192511A - Reading or Recording Apparatus - Google Patents

Abstract

1,192,511. Recording and playback. INTERNATIONAL BUSINESS MACHINES CORP. 8 Jan., 1968 [13 Jan., 1967], No. 1039/68. Heading G5R. [Also in Division F2] Reversing gearing for traversing a transducer 25 across a record card comprises an electric motor 46 which is pivotally mounted so that its output shaft 45 selectively frictionally engages discs 38, 39 on a lead screw 34 to rotate it in opposite directions and effect movement of the transducer assembly 26. The motor 46 is held in its end positions by permanent magnets 53, 54 co-operating with magnetic elements associated with the motor. The transducer assembly carries a member 36 which engages arms 87, 88 of an escapement link 84 at the ends of its travel. The escapement link 84 is thereby shifted a limited amount to permit transverse stepping of the entire mechanism so far described, further rotation of the lead screw shifting it axially to take up play 124 between it and bushing assemblies 56, 57 in which it is mounted. This axial movement of the lead screw causes the motor to pivot to its alternative position in which it is retained by the other magnet 53 or 54 with its shaft 45 engaging the other friction disc to reverse the rotation of the lead screw. The mechanism so far described is mounted on a carriage guided on rails 61 and urged leftwardly of Fig. 2 by a spring. The escapement mechanism comprises a pivoted forked member 75 embracing a screw 79, each limb of the fork having a tooth selectively engageable with the screw. On movement of the escapement link 84 the member 75 is pivoted to release one tooth from the screw 79 and engage the other tooth therewith thus permitting the carriage to be traversed by half the pitch of the screw. The transducer is thus traversed back and forth across the record card and is stepped axially between each traverse. The member 75 can be released from the screw 79 by manual depression of a button 12 on the member to permit the spring to traverse the carriage to a desired location. Back spacing is provided by a bell-crank lever 95 which is pivoted at 96, and also with play at 98, to the carriage. On depression of a button 13 on the lever it first pivots about 96 to engage a pawl 95b with the screw 79 whereafter the lever pivots about the pawl thus shifting the carriage reversely with the member 75 ratcheting on the screw. The record card may have a photographic area for projection of a visual scene and may be perforated for sensing of other information.